The final Halloween Houdini seance was October 31, 1936 (the tenth anniversary of Harry Houdini's death), on the roof of the Knickerbocker Hotel in Hollywood. This was the greatest attempt to contact a spirit. Houdini's widow made her final effort to reach her husband, Harry Houdini, after his death, according to an elaborate plan that they had agreed to, that whichever of them died first would try for ten years to get in touch with the other, on the other (living) side. Although Harry Houdini was known as an antagonist to the spiritualists, he seems to have wanted to believe that it was possible for the living and the dead to communicate, but he demanded proof. Some 300 invited guests formed the outer circle, with 13 scientists, specialists in the occult, reporters, magicians, and spiritual leaders joining Mrs. Houdini in an inner circle. This documentary recording is narrated by George L. Boston. The voice of Mrs. Harry Houdini is included.